1. Field of the Invention
The present invention relates to a liquid crystal display and a method of inspecting the same, and more particularly to a liquid crystal display provided with a driver LSI for driving display elements and a method of inspecting the same.
2. Description of the Background Art
In terms of size-reduction and cost-reduction, in many cases, a COG (Chip On Glass) method is adopted in a liquid crystal display, where bumps of a driver LSI are directly connected to electrode terminals of wires provided on a glass substrates. In the liquid crystal display adopting the COG method or the like, when a display failure such as a line defect is found, it is necessary to judge whether the cause of failure lies in the driver LSI or in the wire.
Since the wires are covered with an insulating layer except terminals connected to the bumps of the driver LSI, however, it has not been easy to investigate the cause of display failure. Then, as a solving means, for example, a means disclosed in Patent Document 1, Japanese Patent Application Laid Open Gazette No. 2000-321591, has been suggested. In Patent Document 1, an output-side wire connected to the driver LSI on board is extended, passing through the lower part of the driver LSI. An electrode portion is formed in the extended output-side wire in the vicinity of an end of a panel, i.e., in an outer portion of the long side of the driver LSI, and check of connection of the driver LSI and check of waveform are performed by using this electrode, to thereby investigate the cause of display failure.
In the case of connection shown in Patent Document 1, since it is necessary to place an input-side wire connected to the driver LSI at a position where the input-side wire does not intersect the output-side wire, the input-side wire should be necessarily connected to a short side of the driver LSI. The shortest-distance connection could have been achieved since the input-side wire is originally connected to a long side of the driver LSI opposite to its long side to which the output-side wire is connected. When the input-side wire is extended, going around the output-side wire, and connected to the short side of the driver LSI, the input-side wire is routed long and this increases wire resistance and disadvantageously causes deterioration of input signals and power supply.
Further, as shown in Patent Document 1, the electrode portion formed in the extended output-side wire is always exposed. When there is an exposed electrode, this causes a problem of inducing corrosion of wires.